The invention relates generally to computer systems, and deals more particularly with a system, method and program product for authenticating an e-mail and/or an attachment to the e-mail.
Electronic mail or “e-mail” is common today. One problem with e-mail is proving to the recipient that the sender of an e-mail (with or without an attachment) is the person indicated as the sender. It was known to superimpose an image of a human signature or facial portrait to an e-mail to prove that the sender of the e-mail is the author of the e-mail. The signature image is thereby sent with the e-mail to the intended recipient. See for example, Japanese Published Unexamined Patent Application #2001-125846. One problem with this technique is that a forger who has access to the signature image can copy the signature image onto another e-mail authored by the forger. Also, nothing prevents the recipient of the e-mail from detaching an attachment (for example, a data file) to the e-mail, attaching it to another e-mail, and transferring the attachment as his or her own work to others with this other e-mail. In such a case, the recipient of this other e-mail with the attachment cannot be sure that the sender of this other e-mail authored the attachment.
Accordingly, an object of the present invention is to discourage forgery of e-mails.
Another object of the present invention is to authenticate the author of an e-mail.
Another object of the present invention is to authenticate the author of an attachment to an e-mail.
Another object of the present invention is to enable tracing of an original sender and original receiver of an e-mail and/or an attachment to the e-mail.